<?php
/* vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4: */

/**
* Converts to and from JSON format.
*
* JSON (JavaScript Object Notation) is a lightweight data-interchange
* format. It is easy for humans to read and write. It is easy for machines
* to parse and generate. It is based on a subset of the JavaScript
* Programming Language, Standard ECMA-262 3rd Edition - December 1999.
* This feature can also be found in  Python. JSON is a text format that is
* completely language independent but uses conventions that are familiar
* to programmers of the C-family of languages, including C, C++, C#, Java,
* JavaScript, Perl, TCL, and many others. These properties make JSON an
* ideal data-interchange language.
*
* This package provides a simple encoder and decoder for JSON notation. It
* is intended for use with client-side Javascript applications that make
* use of HTTPRequest to perform server communication functions - data can
* be encoded into JSON notation for use in a client-side javascript, or
* decoded from incoming Javascript requests. JSON format is native to
* Javascript, and can be directly eval()'ed with no further parsing
* overhead
*
* All strings should be in ASCII or UTF-8 format!
*
* LICENSE: Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met: Redistributions of source code must retain the
* above copyright notice, this list of conditions and the following
* disclaimer. Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
* NO EVENT SHALL CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
* TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
* USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*
* @category
* @package     Services_JSON
* @author      Michal Migurski <mike-json@teczno.com>
* @author      Matt Knapp <mdknapp[at]gmail[dot]com>
* @author      Brett Stimmerman <brettstimmerman[at]gmail[dot]com>
* @copyright   2005 Michal Migurski
* @version     CVS: $Id: JSON.php,v 1.31 2006/06/28 05:54:17 migurski Exp $
* @license     http://www.opensource.org/licenses/bsd-license.php
* @link        http://pear.php.net/pepr/pepr-proposal-show.php?id=198
*/

/**
* Marker constant for Services_JSON::decode(), used to flag stack state
*/
define('SERVICES_JSON_SLICE',   1);

/**
* Marker constant for Services_JSON::decode(), used to flag stack state
*/
define('SERVICES_JSON_IN_STR',  2);

/**
* Marker constant for Services_JSON::decode(), used to flag stack state
*/
define('SERVICES_JSON_IN_ARR',  3);

/**
* Marker constant for Services_JSON::decode(), used to flag stack state
*/
define('SERVICES_JSON_IN_OBJ',  4);

/**
* Marker constant for Services_JSON::decode(), used to flag stack state
*/
define('SERVICES_JSON_IN_CMT', 5);

/**
* Behavior switch for Services_JSON::decode()
*/
define('SERVICES_JSON_LOOSE_TYPE', 16);

/**
* Behavior switch for Services_JSON::decode()
*/
define('SERVICES_JSON_SUPPRESS_ERRORS', 32);

/**
 * Converts to and from JSON format.
 *
 * @example <code>
 	// create a new instance of Services_JSON
 	$json = new Services_JSON();
	
 	// convert a complexe value to JSON notation, and send it to the browser
 	$value = array('foo', 'bar', array(1, 2, 'baz'), array(3, array(4)));
 	$output = $json->encode($value);
	
 	print($output);
 	// prints: ["foo","bar",[1,2,"baz"],[3,[4]]]
	
 	// accept incoming POST data, assumed to be in JSON notation
 	$input = file_get_contents('php://input', 1000000);
 	$value = $json->decode($input);
 	</code>
 *
 */
class Services_JSON
{
 	/**
		* constructs a new JSON instance
		*
		* @param    int     $use    object behavior flags; combine with boolean-OR
		*
		*                           possible values:
		*                           - SERVICES_JSON_LOOSE_TYPE:  loose typing.
		*                                   "{...}" syntax creates associative arrays
		*                                   instead of objects in decode().
		*                           - SERVICES_JSON_SUPPRESS_ERRORS:  error suppression.
		*                                   Values which can't be encoded (e.g. resources)
		*                                   appear as NULL instead of throwing errors.
		*                                   By default, a deeply-nested resource will
		*                                   bubble up with an error, so all return values
		*                                   from encode() should be checked with isError()
		*/
		function Services_JSON($use = 0)
		{
				$this->use = $use;
		}

 	/**
		* convert a string from one UTF-16 char to one UTF-8 char
		*
		* Normally should be handled by mb_convert_encoding, but
		* provides a slower PHP-only method for installations
		* that lack the multibye string extension.
		*
		* @param    string  $utf16  UTF-16 character
		* @return   string  UTF-8 character
		* @access   private
		*/
		function utf162utf8($utf16)
		{
				// oh please oh please oh please oh please oh please
				if(function_exists('mb_convert_encoding')) {
						return mb_convert_encoding($utf16, 'UTF-8', 'UTF-16');
				}

				$bytes = (ord($utf16{0}) << 8) | ord($utf16{1});

				switch(true) {
						case ((0x7F & $bytes) == $bytes):
								// this case should never be reached, because we are in ASCII range
								// see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
								return chr(0x7F & $bytes);

						case (0x07FF & $bytes) == $bytes:
								// return a 2-byte UTF-8 character
								// see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
								return chr(0xC0 | (($bytes >> 6) & 0x1F))
 										. chr(0x80 | ($bytes & 0x3F));

						case (0xFFFF & $bytes) == $bytes:
								// return a 3-byte UTF-8 character
								// see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
								return chr(0xE0 | (($bytes >> 12) & 0x0F))
 										. chr(0x80 | (($bytes >> 6) & 0x3F))
 										. chr(0x80 | ($bytes & 0x3F));
				}

				// ignoring UTF-32 for now, sorry
				return '';
		}

 	/**
		* convert a string from one UTF-8 char to one UTF-16 char
		*
		* Normally should be handled by mb_convert_encoding, but
		* provides a slower PHP-only method for installations
		* that lack the multibye string extension.
		*
		* @param    string  $utf8   UTF-8 character
		* @return   string  UTF-16 character
		* @access   private
		*/
		function utf82utf16($utf8)
		{
				// oh please oh please oh please oh please oh please
				if(function_exists('mb_convert_encoding')) {
						return mb_convert_encoding($utf8, 'UTF-16', 'UTF-8');
				}

				switch(strlen($utf8)) {
						case 1:
								// this case should never be reached, because we are in ASCII range
								// see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
								return $utf8;

						case 2:
								// return a UTF-16 character from a 2-byte UTF-8 char
								// see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
								return chr(0x07 & (ord($utf8{0}) >> 2))
 										. chr((0xC0 & (ord($utf8{0}) << 6))
 												| (0x3F & ord($utf8{1})));

						case 3:
								// return a UTF-16 character from a 3-byte UTF-8 char
								// see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
								return chr((0xF0 & (ord($utf8{0}) << 4))
 												| (0x0F & (ord($utf8{1}) >> 2)))
 										. chr((0xC0 & (ord($utf8{1}) << 6))
 												| (0x7F & ord($utf8{2})));
				}

				// ignoring UTF-32 for now, sorry
				return '';
		}

 	/**
		* encodes an arbitrary variable into JSON format
		*
		* @param    mixed   $var    any number, boolean, string, array, or object to be encoded.
		*                           see argument 1 to Services_JSON() above for array-parsing behavior.
		*                           if var is a strng, note that encode() always expects it
		*                           to be in ASCII or UTF-8 format!
		*
		* @return   mixed   JSON string representation of input var or an error if a problem occurs
		* @access   public
		*/
		function encode($var)
		{
				switch (gettype($var)) {
						case 'boolean':
								return $var ? 'true' : 'false';

						case 'NULL':
								return 'null';

						case 'integer':
								return (int) $var;

						case 'double':
						case 'float':
								return (float) $var;

						case 'string':
								// STRINGS ARE EXPECTED TO BE IN ASCII OR UTF-8 FORMAT
								$ascii = '';
								$strlen_var = strlen($var);

 							/*
								* Iterate over every character in the string,
								* escaping with a slash or encoding to UTF-8 where necessary
								*/
								for ($c = 0; $c < $strlen_var; ++$c) {

										$ord_var_c = ord($var{$c});

										switch (true) {
												case $ord_var_c == 0x08:
														$ascii .= '\b';
														break;
												case $ord_var_c == 0x09:
														$ascii .= '\t';
														break;
												case $ord_var_c == 0x0A:
														$ascii .= '\n';
														break;
												case $ord_var_c == 0x0C:
														$ascii .= '\f';
														break;
												case $ord_var_c == 0x0D:
														$ascii .= '\r';
														break;

												case $ord_var_c == 0x22:
												case $ord_var_c == 0x2F:
												case $ord_var_c == 0x5C:
														// double quote, slash, slosh
														$ascii .= '\\'.$var{$c};
														break;

												case (($ord_var_c >= 0x20) && ($ord_var_c <= 0x7F)):
														// characters U-00000000 - U-0000007F (same as ASCII)
														$ascii .= $var{$c};
														break;

												case (($ord_var_c & 0xE0) == 0xC0):
														// characters U-00000080 - U-000007FF, mask 110XXXXX
														// see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
														$char = pack('C*', $ord_var_c, ord($var{$c + 1}));
														$c += 1;
														$utf16 = $this->utf82utf16($char);
														$ascii .= sprintf('\u%04s', bin2hex($utf16));
														break;

												case (($ord_var_c & 0xF0) == 0xE0):
														// characters U-00000800 - U-0000FFFF, mask 1110XXXX
														// see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
														$char = pack('C*', $ord_var_c,
 																				ord($var{$c + 1}),
 																				ord($var{$c + 2}));
														$c += 2;
														$utf16 = $this->utf82utf16($char);
														$ascii .= sprintf('\u%04s', bin2hex($utf16));
														break;

												case (($ord_var_c & 0xF8) == 0xF0):
														// characters U-00010000 - U-001FFFFF, mask 11110XXX
														// see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
														$char = pack('C*', $ord_var_c,
 																				ord($var{$c + 1}),
 																				ord($var{$c + 2}),
 																				ord($var{$c + 3}));
														$c += 3;
														$utf16 = $this->utf82utf16($char);
														$ascii .= sprintf('\u%04s', bin2hex($utf16));
														break;

												case (($ord_var_c & 0xFC) == 0xF8):
														// characters U-00200000 - U-03FFFFFF, mask 111110XX
														// see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
														$char = pack('C*', $ord_var_c,
 																				ord($var{$c + 1}),
 																				ord($var{$c + 2}),
 																				ord($var{$c + 3}),
 																				ord($var{$c + 4}));
														$c += 4;
														$utf16 = $this->utf82utf16($char);
														$ascii .= sprintf('\u%04s', bin2hex($utf16));
														break;

												case (($ord_var_c & 0xFE) == 0xFC):
														// characters U-04000000 - U-7FFFFFFF, mask 1111110X
														// see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
														$char = pack('C*', $ord_var_c,
 																				ord($var{$c + 1}),
 																				ord($var{$c + 2}),
 																				ord($var{$c + 3}),
 																				ord($var{$c + 4}),
 																				ord($var{$c + 5}));
														$c += 5;
														$utf16 = $this->utf82utf16($char);
														$ascii .= sprintf('\u%04s', bin2hex($utf16));
														break;
										}
								}

								return '"'.$ascii.'"';

						case 'array':
 							/*
								* As per JSON spec if any array key is not an integer
								* we must treat the the whole array as an object. We
								* also try to catch a sparsely populated associative
								* array with numeric keys here because some JS engines
								* will create an array with empty indexes up to
								* max_index which can cause memory issues and because
								* the keys, which may be relevant, will be remapped
								* otherwise.
								*
								* As per the ECMA and JSON specification an object may
								* have any string as a property. Unfortunately due to
								* a hole in the ECMA specification if the key is a
								* ECMA reserved word or starts with a digit the
								* parameter is only accessible using ECMAScript's
								* bracket notation.
								*/

								// treat as a JSON object
								if (is_array($var) && count($var) && (array_keys($var) !== range(0, sizeof($var) - 1))) {
										$properties = array_map(array($this, 'name_value'),
																						array_keys($var),
																						array_values($var));

										foreach($properties as $property) {
												if(Services_JSON::isError($property)) {
														return $property;
												}
										}

										return '{' . join(',', $properties) . '}';
								}

								// treat it like a regular array
								$elements = array_map(array($this, 'encode'), $var);

								foreach($elements as $element) {
										if(Services_JSON::isError($element)) {
												return $element;
										}
								}

								return '[' . join(',', $elements) . ']';

						case 'object':
								$vars = get_object_vars($var);

								$properties = array_map(array($this, 'name_value'),
																				array_keys($vars),
																				array_values($vars));

								foreach($properties as $property) {
										if(Services_JSON::isError($property)) {
												return $property;
										}
								}

								return '{' . join(',', $properties) . '}';

						default:
								return ($this->use & SERVICES_JSON_SUPPRESS_ERRORS)
										? 'null'
										: new Services_JSON_Error(gettype($var)." can not be encoded as JSON string");
				}
		}

 	/**
		* array-walking function for use in generating JSON-formatted name-value pairs
		*
		* @param    string  $name   name of key to use
		* @param    mixed   $value  reference to an array element to be encoded
		*
		* @return   string  JSON-formatted name-value pair, like '"name":value'
		* @access   private
		*/
		function name_value($name, $value)
		{
				$encoded_value = $this->encode($value);

				if(Services_JSON::isError($encoded_value)) {
						return $encoded_value;
				}

				return $this->encode(strval($name)) . ':' . $encoded_value;
		}

 	/**
		* reduce a string by removing leading and trailing comments and whitespace
		*
		* @param    $str    string      string value to strip of comments and whitespace
		*
		* @return   string  string value stripped of comments and whitespace
		* @access   private
		*/
		function reduce_string($str)
		{
				$str = preg_replace(array(

								// eliminate single line comments in '// ...' form
								'#^\s*//(.+)$#m',

								// eliminate multi-line comments in '/* ... */' form, at start of string
								'#^\s*/\*(.+)\*/#Us',

								// eliminate multi-line comments in '/* ... */' form, at end of string
								'#/\*(.+)\*/\s*$#Us'

						), '', $str);

				// eliminate extraneous space
				return trim($str);
		}

 	/**
		* decodes a JSON string into appropriate variable
		*
		* @param    string  $str    JSON-formatted string
		*
		* @return   mixed   number, boolean, string, array, or object
		*                   corresponding to given JSON input string.
		*                   See argument 1 to Services_JSON() above for object-output behavior.
		*                   Note that decode() always returns strings
		*                   in ASCII or UTF-8 format!
		* @access   public
		*/
		function decode($str)
		{
				$str = $this->reduce_string($str);

				switch (strtolower($str)) {
						case 'true':
								return true;

						case 'false':
								return false;

						case 'null':
								return null;

						default:
								$m = array();

								if (is_numeric($str)) {
										// Lookie-loo, it's a number

										// This would work on its own, but I'm trying to be
										// good about returning integers where appropriate:
										// return (float)$str;

										// Return float or int, as appropriate
										return ((float)$str == (integer)$str)
												? (integer)$str
												: (float)$str;

								} elseif (preg_match('/^("|\').*(\1)$/s', $str, $m) && $m[1] == $m[2]) {
										// STRINGS RETURNED IN UTF-8 FORMAT
										$delim = substr($str, 0, 1);
										$chrs = substr($str, 1, -1);
										$utf8 = '';
										$strlen_chrs = strlen($chrs);

										for ($c = 0; $c < $strlen_chrs; ++$c) {

												$substr_chrs_c_2 = substr($chrs, $c, 2);
												$ord_chrs_c = ord($chrs{$c});

												switch (true) {
														case $substr_chrs_c_2 == '\b':
																$utf8 .= chr(0x08);
																++$c;
																break;
														case $substr_chrs_c_2 == '\t':
																$utf8 .= chr(0x09);
																++$c;
																break;
														case $substr_chrs_c_2 == '\n':
																$utf8 .= chr(0x0A);
																++$c;
																break;
														case $substr_chrs_c_2 == '\f':
																$utf8 .= chr(0x0C);
																++$c;
																break;
														case $substr_chrs_c_2 == '\r':
																$utf8 .= chr(0x0D);
																++$c;
																break;

														case $substr_chrs_c_2 == '\\"':
														case $substr_chrs_c_2 == '\\\'':
														case $substr_chrs_c_2 == '\\\\':
														case $substr_chrs_c_2 == '\\/':
																if (($delim == '"' && $substr_chrs_c_2 != '\\\'') ||
 																	($delim == "'" && $substr_chrs_c_2 != '\\"')) {
																		$utf8 .= $chrs{++$c};
																}
																break;

														case preg_match('/\\\u[0-9A-F]{4}/i', substr($chrs, $c, 6)):
																// single, escaped unicode character
																$utf16 = chr(hexdec(substr($chrs, ($c + 2), 2)))
 																			. chr(hexdec(substr($chrs, ($c + 4), 2)));
																$utf8 .= $this->utf162utf8($utf16);
																$c += 5;
																break;

														case ($ord_chrs_c >= 0x20) && ($ord_chrs_c <= 0x7F):
																$utf8 .= $chrs{$c};
																break;

														case ($ord_chrs_c & 0xE0) == 0xC0:
																// characters U-00000080 - U-000007FF, mask 110XXXXX
																//see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
																$utf8 .= substr($chrs, $c, 2);
																++$c;
																break;

														case ($ord_chrs_c & 0xF0) == 0xE0:
																// characters U-00000800 - U-0000FFFF, mask 1110XXXX
																// see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
																$utf8 .= substr($chrs, $c, 3);
																$c += 2;
																break;

														case ($ord_chrs_c & 0xF8) == 0xF0:
																// characters U-00010000 - U-001FFFFF, mask 11110XXX
																// see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
																$utf8 .= substr($chrs, $c, 4);
																$c += 3;
																break;

														case ($ord_chrs_c & 0xFC) == 0xF8:
																// characters U-00200000 - U-03FFFFFF, mask 111110XX
																// see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
																$utf8 .= substr($chrs, $c, 5);
																$c += 4;
																break;

														case ($ord_chrs_c & 0xFE) == 0xFC:
																// characters U-04000000 - U-7FFFFFFF, mask 1111110X
																// see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
																$utf8 .= substr($chrs, $c, 6);
																$c += 5;
																break;

												}

										}

										return $utf8;

								} elseif (preg_match('/^\[.*\]$/s', $str) || preg_match('/^\{.*\}$/s', $str)) {
										// array, or object notation

										if ($str{0} == '[') {
												$stk = array(SERVICES_JSON_IN_ARR);
												$arr = array();
										} else {
												if ($this->use & SERVICES_JSON_LOOSE_TYPE) {
														$stk = array(SERVICES_JSON_IN_OBJ);
														$obj = array();
												} else {
														$stk = array(SERVICES_JSON_IN_OBJ);
														$obj = new stdClass();
												}
										}

										array_push($stk, array('what'  => SERVICES_JSON_SLICE,
 																					'where' => 0,
 																					'delim' => false));

										$chrs = substr($str, 1, -1);
										$chrs = $this->reduce_string($chrs);

										if ($chrs == '') {
												if (reset($stk) == SERVICES_JSON_IN_ARR) {
														return $arr;

												} else {
														return $obj;

												}
										}

										//print("\nparsing {$chrs}\n");

										$strlen_chrs = strlen($chrs);

										for ($c = 0; $c <= $strlen_chrs; ++$c) {

												$top = end($stk);
												$substr_chrs_c_2 = substr($chrs, $c, 2);

												if (($c == $strlen_chrs) || (($chrs{$c} == ',') && ($top['what'] == SERVICES_JSON_SLICE))) {
														// found a comma that is not inside a string, array, etc.,
														// OR we've reached the end of the character list
														$slice = substr($chrs, $top['where'], ($c - $top['where']));
														array_push($stk, array('what' => SERVICES_JSON_SLICE, 'where' => ($c + 1), 'delim' => false));
														//print("Found split at {$c}: ".substr($chrs, $top['where'], (1 + $c - $top['where']))."\n");

														if (reset($stk) == SERVICES_JSON_IN_ARR) {
																// we are in an array, so just push an element onto the stack
																array_push($arr, $this->decode($slice));

														} elseif (reset($stk) == SERVICES_JSON_IN_OBJ) {
																// we are in an object, so figure
																// out the property name and set an
																// element in an associative array,
																// for now
																$parts = array();
																
																if (preg_match('/^\s*(["\'].*[^\\\]["\'])\s*:\s*(\S.*),?$/Uis', $slice, $parts)) {
																		// "name":value pair
																		$key = $this->decode($parts[1]);
																		$val = $this->decode($parts[2]);

																		if ($this->use & SERVICES_JSON_LOOSE_TYPE) {
																				$obj[$key] = $val;
																		} else {
																				$obj->$key = $val;
																		}
																} elseif (preg_match('/^\s*(\w+)\s*:\s*(\S.*),?$/Uis', $slice, $parts)) {
																		// name:value pair, where name is unquoted
																		$key = $parts[1];
																		$val = $this->decode($parts[2]);

																		if ($this->use & SERVICES_JSON_LOOSE_TYPE) {
																				$obj[$key] = $val;
																		} else {
																				$obj->$key = $val;
																		}
																}

														}

												} elseif ((($chrs{$c} == '"') || ($chrs{$c} == "'")) && ($top['what'] != SERVICES_JSON_IN_STR)) {
														// found a quote, and we are not inside a string
														array_push($stk, array('what' => SERVICES_JSON_IN_STR, 'where' => $c, 'delim' => $chrs{$c}));
														//print("Found start of string at {$c}\n");

												} elseif (($chrs{$c} == $top['delim']) &&
 																($top['what'] == SERVICES_JSON_IN_STR) &&
 																((strlen(substr($chrs, 0, $c)) - strlen(rtrim(substr($chrs, 0, $c), '\\'))) % 2 != 1)) {
														// found a quote, we're in a string, and it's not escaped
														// we know that it's not escaped becase there is _not_ an
														// odd number of backslashes at the end of the string so far
														array_pop($stk);
														//print("Found end of string at {$c}: ".substr($chrs, $top['where'], (1 + 1 + $c - $top['where']))."\n");

												} elseif (($chrs{$c} == '[') &&
 																in_array($top['what'], array(SERVICES_JSON_SLICE, SERVICES_JSON_IN_ARR, SERVICES_JSON_IN_OBJ))) {
														// found a left-bracket, and we are in an array, object, or slice
														array_push($stk, array('what' => SERVICES_JSON_IN_ARR, 'where' => $c, 'delim' => false));
														//print("Found start of array at {$c}\n");

												} elseif (($chrs{$c} == ']') && ($top['what'] == SERVICES_JSON_IN_ARR)) {
														// found a right-bracket, and we're in an array
														array_pop($stk);
														//print("Found end of array at {$c}: ".substr($chrs, $top['where'], (1 + $c - $top['where']))."\n");

												} elseif (($chrs{$c} == '{') &&
 																in_array($top['what'], array(SERVICES_JSON_SLICE, SERVICES_JSON_IN_ARR, SERVICES_JSON_IN_OBJ))) {
														// found a left-brace, and we are in an array, object, or slice
														array_push($stk, array('what' => SERVICES_JSON_IN_OBJ, 'where' => $c, 'delim' => false));
														//print("Found start of object at {$c}\n");

												} elseif (($chrs{$c} == '}') && ($top['what'] == SERVICES_JSON_IN_OBJ)) {
														// found a right-brace, and we're in an object
														array_pop($stk);
														//print("Found end of object at {$c}: ".substr($chrs, $top['where'], (1 + $c - $top['where']))."\n");

												} elseif (($substr_chrs_c_2 == '/*') &&
 																in_array($top['what'], array(SERVICES_JSON_SLICE, SERVICES_JSON_IN_ARR, SERVICES_JSON_IN_OBJ))) {
														// found a comment start, and we are in an array, object, or slice
														array_push($stk, array('what' => SERVICES_JSON_IN_CMT, 'where' => $c, 'delim' => false));
														$c++;
														//print("Found start of comment at {$c}\n");

												} elseif (($substr_chrs_c_2 == '*/') && ($top['what'] == SERVICES_JSON_IN_CMT)) {
														// found a comment end, and we're in one now
														array_pop($stk);
														$c++;

														for ($i = $top['where']; $i <= $c; ++$i)
																$chrs = substr_replace($chrs, ' ', $i, 1);

														//print("Found end of comment at {$c}: ".substr($chrs, $top['where'], (1 + $c - $top['where']))."\n");

												}

										}

										if (reset($stk) == SERVICES_JSON_IN_ARR) {
												return $arr;

										} elseif (reset($stk) == SERVICES_JSON_IN_OBJ) {
												return $obj;

										}

								}
				}
		}

		/**
 		* @todo Ultimately, this should just call PEAR::isError()
 		*/
		function isError($data, $code = null)
		{
				if (class_exists('pear')) {
						return PEAR::isError($data, $code);
				} elseif (is_object($data) && (get_class($data) == 'services_json_error' ||
 																is_subclass_of($data, 'services_json_error'))) {
						return true;
				}

				return false;
		}
}

if (class_exists('PEAR_Error')) {

		class Services_JSON_Error extends PEAR_Error
		{
				function Services_JSON_Error($message = 'unknown error', $code = null,
 																		$mode = null, $options = null, $userinfo = null)
				{
						parent::PEAR_Error($message, $code, $mode, $options, $userinfo);
				}
		}

} else {

		/**
 		* @todo Ultimately, this class shall be descended from PEAR_Error
 		*/
		class Services_JSON_Error
		{
				function Services_JSON_Error($message = 'unknown error', $code = null,
 																		$mode = null, $options = null, $userinfo = null)
				{

				}
		}

}
		
?>